public void ContainsEdgeTest1()
        {
            var bd = new BidirectionalGraph <int, IEdge <int> >();

            var e12 = new SEquatableUndirectedEdge <int>(1, 2);
            var f12 = new SEquatableUndirectedEdge <int>(1, 2);

            bd.AddVerticesAndEdge(e12);

            ContainsEdgeAssertions(bd, e12, f12, null, null);

            var u = new UndirectedBidirectionalGraph <int, IEdge <int> >(bd);

            UndirectedGraphTest.ContainsEdgeAssertions(u, e12, f12, null, null);
        }
        public void ContainsEdgeTest2()
        {
            var bd = new BidirectionalGraph <int, IEdge <int> >();

            var e12 = new EquatableEdge <int>(1, 2);
            var f12 = new EquatableEdge <int>(1, 2);
            var e21 = new EquatableEdge <int>(2, 1);
            var f21 = new EquatableEdge <int>(2, 1);

            bd.AddVerticesAndEdge(e12);

            ContainsEdgeAssertions(bd, e12, f12, e21, f21);

            var u = new UndirectedBidirectionalGraph <int, IEdge <int> >(bd);

            UndirectedGraphTest.ContainsEdgeAssertions(u, e12, f12, e21, f21);
        }